Electrophoretic separation of particle fractions, especially protein fractions, in microfluid system with independently controllable flow of auxiliary buffer in control channel and sample buffer in sample channel

摘要

Electrophoretic separation of a particle fraction in a microfluid system with microchannels involves: (i) passing an auxiliary buffer (AB) through a control channel (CC) (22); (ii) passing a sample medium (SM) (i.e. sample buffer (SB) plus sample particles (SP)) through a sample channel (SC) (21), running in the longitudinal direction of CC and separated from CC by an intermediate region of material (27) permeable to electrically charged particles from SB and optionally at least part of SP; (iii) creating a pH gradient in SC transverse to the flowing SM, in an electric field applied transverse to CC, using AB flowing in CC and SB flowing in SC; and (iv) electrophoretically separating a particle fraction of SP in SC via the pH gradient, utilizing the electric field.